Meaning of “contraction” - Learner’s Dictionary

contraction

noun uk us /kənˈtrækʃən/
MUSCLE [ C ]

a strong, painful movement of the muscles that a woman has when she is having a baby:

She was having contractions every ten minutes.
WORD [ C ]

a short form of a word or group of words:

'Won't' is a contraction of 'will not'.
REDUCTION [ U ]

an action in which something becomes smaller or shorter

(Definition of “contraction” from the Cambridge Learner’s Dictionary © Cambridge University Press)